Older blog entries for asmodai (starting at number 39)

On design

Maybe this will reach some people and cause less frustration for other people:

  • No, Microsoft Word is not the correct kind of program to design your logo in.
  • When your designer asks for a high resolution copy of your logo, he means something that not 150 x 300 pixels, but rather a logo professionally designed with a vector drawing program, say, Adobe Illustrator.
  • Despite how creative your designer is, he or she need input and ideas about what you want to accomplish in order to give you results in return.
  • Designing a logo that you feel comfortable with can take as little as 1 hour or as long as a few days or even weeks (depending on the amount of people who have to affirm it), you have to pay for such effort, obviously.
  • The primary colours are blue, green, and red (unless we are talking about print, then they are cyan, magenta, and yellow).
  • No, blue is not a warm colour. Subsequently, red is not a cool colour.
  • After you have approved all designs, changing your mind means you will incur additional costs.
  • You cannot just take photos or other images/designs from the Internet and reuse them without clearing proper copyright issues.

Syndicated 2010-02-17 13:40:56 from In Nomine - The Lotus Land

Clustering and relevant algorithms

Disclaimer: I’m mainland European, we tend to use the , to separate digits from the whole numbers.

Clustering is quite a common approach to aggregate coordinates that are relatively close together. The problem lies in the choice of algorithm to use. This choice is highly dependent on the space in which the coordinates are laid out. Quite often you can just use basic Euclidean distance which, for a 2-dimensional space, simply takes the square root of the sum of the squared subtraction of the respective coordinates of each point. So if you have a point p with coordinates (33, 52) and a point q with coordinates (82, 19), the distance between p and q would be:

>>> import math
>>> math.sqrt(pow(33 - 82, 2) + pow(52 - 19, 2))
59.076221950967721

And based on that distance you can start to cluster points together that are all roughly the same distance from a certain point, say 59,1. The fun part of this is that this distance is the radius of a circle. So if you would plot every possible coordinate at that distance you will see a circle emerge.

In looking at clustering algorithms I also encountered something called Manhattan distance, but this algorithm only makes sense if you are working in a grid with roughly equidistant lengths to the other coordinates in this space. Normally the shortest distance from A to B would be a straight line, as the Euclidean distance shows. However, if the movement from coordinate to coordinate is restricted to straight lines, say the grid layout of a lot of North American cities, then Euclidean distance cannot apply. This is the same problem a taxi faces when trying to find the shortest distance to drive from A to B and as such the algorithm is also known as the taxicab distance or geometry. It takes the sum of the absolute value of the subtraction of the respective coordinates of each point. So if you take point p and q again, the distance would in this case be:

>>> abs(33 - 82) + abs(52 - 19)
82

Now, if you would plot all possible coordinates with that distance you will see a circle emerge again. However, keep in mind that a circle is nothing more than a set of points with a fixed distance (the radius). In this case our geometry uses a differently defined distance. If you would plot this out with a finer and finer grid the circle shape that emerges is a square rotated 45° so that it rests on its point.

Syndicated 2010-01-18 11:35:38 from In Nomine - The Lotus Land

OpenGL 3.x and DirectX 10/11

Expect more information about OpenGL and DirectX related subjects in the coming period as I will start to delve into the basics of these.

Syndicated 2010-01-18 10:30:06 from In Nomine - The Lotus Land

Avatar 3D, blurry vision

Went to see Avatar in 3D tonight. Typical story, but the animation was amazing. The 3D was also better than what has been out there. But darn, for the past 4 hours after exiting the theatre I have been having my vision still be in stereoscopic mode or something. I see everything beyond 1-2 meters as blurry, as if watching the movie without glasses. Hope a good night’s rest will cure that.

Syndicated 2009-12-30 22:45:47 from In Nomine - The Lotus Land

Finally a stable connection

As I previously recorded in the posts here and here, my network interface card under Windows 7 started to drop the complete traffic whenever it got stressed out with network traffic. Heck, sometimes not even when stressing it out. Digging through various fora I came to the Nvidia forum again and found a thread that mentioned a Microsoft Knowledge Base article that instructs in turning off receive-side scaling.

After turning said option off and stress testing the link for a few hours I did not experience any drops. So this might actually finally be the stable connection I am looking for.

Syndicated 2009-12-16 06:47:01 from In Nomine - The Lotus Land

CLDR 1.8 data submission closing

The data submission phase for CLDR 1.8 should be closed by now (although the survey tool still says it’s accepting submissions). For Dutch (nl_NL), I’ve been going over quite some items together with the Apple contributor and someone else, so expect quite some improvements on that area. The current release date is aimed at somewhere in March 2010.

Syndicated 2009-12-03 15:26:30 from In Nomine - The Lotus Land

Google’s Japanese IME

Google has released an input method editor (IME) for Japanese in a similar style as their Chinese IME. It can be found on their IME page. It looks to be available for Mac OS X, Windows XP SP2, Vista SP1, and Windows 7.

Syndicated 2009-12-03 15:22:27 from In Nomine - The Lotus Land

Upgrading dd-wrt for Windows 7, problems and a possible fix?

As noted in my earlier post I had issues with my network interface card (NIC) dropping my connection whimsically.

So finding some posts about possible firmware issues with Linksys routers and disconnects I proceeded to update my router’s firmware from dd-wrt v23 to v24 pre-sp2. This actually caused me some problems. I followed the information presented in the stickies on the dd-wrt forum, which means that prior to updating the firmware I did the 30/30/30 reset to get the factory defaults going again, then proceeded with uploading the new firmware (v24 pre-sp2 build 13064) and once that was done do the 30/30/30 reset again.

And that’s where 2-2,5 hours of frustrating would kick in. After the router had rebooted I couldn’t ping the default 192.168.1.1 address. I was getting a destination unreachable message. So alarm bells started to ring in my head, thinking I had bricked my router in some way. But the strange thing was that it looked like it rebooted correctly, no strange flashing LEDs, or not being responsive to cables being plugged in and taken out. Of course, with the router down I had no Internet connectivity to do some troubleshooting browsing. But thankfully I could use my Android mobile phone for that. I retried various reset routines but to no avail. Of course I started to despair a bit more, thinking I would have to buy a new router. I then noticed that the WLAN LED was lit up. Since my Android phone supports WiFi I figured I should see if it shows up. ‘Lo and behold, it had a network with the SSID ‘dd-wrt’ and sure enough, I could connect to it. Next was trying to router’s web interface and that worked too! Of course that enthusiasm was quickly dampened when I discovered that you cannot do a firmware upgrade over the wireless link. I also couldn’t find any way online on how to override this precautionary lockout, so it was back to square one.

And then I stumbled over a post which mentioned that Linksys routers with the original firmware sometimes have their wired LAN ports revert to 10 Mbit/half-duplex settings. After picking up my jaw from the floor I wondered if it could be so easy. Sure enough, after changing the settings for my NIC in the configuration window, I could ping 192.168.1.1 and load up the administration interface in my browser.

Then I tried my World of Warcraft (WoW) patch download again (which is essentially a BitTorrent client) and stream Bohemian Rhapsody by the Muppets at HD quality from YouTube only to have my NIC go silent on me again. So, after the few hours of futzing with the router and its upgrade I was no closer to a proper solution. Although I did conclude it was, in fact, the Windows 7 box acting up since my WiFi connection as well as the Unix box on another LAN port could still use the network as it should.

Then the morning after I was looking around several Google results again and came to a post on the Windows7Forums.com website where someone had troubles with a wireless connection from Windows 7. I use a wired connection, so aside from the symptoms it’s not quite similar. It then documents the ‘roll back driver’ solution, which I had previously tried. But it became interesting when I found Sage’s post at the bottom which reads:

“I think I’ve found the solution to this problem. It was revealed recently (A week or two ago) that there is a bug in the NVIDIA chipsets when using 64-bit addressing. This ends up affecting a whole host of things on machines, including this nefarious “Random internet disconnect” problem. I posted this solution over at a couple other W7 forums and others with NVIDIA chipsets and 64-bit machines have all found it to succeed in fixing this frustrating issue.

What it more or less comes down to is applying this hotfix: You encounter problems when you move data over USB from a Windows 7 or Windows Server 2008 R2-based computer that has an NVIDIA USB EHCI chipset and at least 4GB of RAM

Ignore the fact that it mentions this fix to be solely for USB hardware issues. It is a fix for the NVIDIA chipset on 64-bit Windows 7 and has been practically a miracle fix for people with the USB harddrive disconnect problem, the random internet drop problem, and the internet-disconnect-on-wake-from-sleep problems that have all been plaguing Windows 7 64-Bit users since the RC.”

Funnily enough my Windows 7 is 64-bits and I also have an NVIDIA nForce chipset. Looking at the hotfix page shows it really is only updated USB driver files. Figuring it cannot possibly be worse than my situation now I installed the hotfix are being emailed the location to download it from. A reboot later I was downloading my WoW patch with the downloader while streaming the Muppets again and haven’t seen it drop dead yet. So initial tests show it might very well be the solution, but I need to stress test it some more.

Syndicated 2009-12-03 10:10:25 from In Nomine - The Lotus Land

Windows 7 and the case of the dropped network traffic

So the good news of Windows 7 is that they removed the TCP half-open limits.

The bad news is that quite a fair number of people have problems with their network interface card (NIC) dropping dead on them as soon as they push their system to sustained high throughput, think of leeching newsgroups, using torrents, but also downloading ISOs (BSD or Linux releases) or even watching YouTube clips and downloading a driver.

The suggested ‘fixes’ have been ranging from absurd to interesting.

Things I have done so far:

  • rolled back the driver from NVIDIA to Microsoft’s stock driver, did NOT help
  • disabled power management features, did NOT help
  • disabled autotuninglevel (netsh int tcp set global autotuninglevel=disabled), still in testing

Things to try still:

  • disable all Quality of Service (QoS) stuff
  • disable all offloading (netsh int ip set global taskoffload=disabled)
  • disable Gigabit related features

Syndicated 2009-12-01 22:30:40 from In Nomine - The Lotus Land

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